bt829bkrf ETC-unknow, bt829bkrf Datasheet - Page 68

• Manufacturer Part Number: bt829bkrf
• Description: Video Streamii Decoders
• Manufacturer: ETC-unknow

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2.0 Electrical Interfaces
2.2 Output Interface
2.2.4 Synchronous Pixel Interface (SPI Mode 2, ByteStream)
In SPI Mode 2, the Bt829B encodes all video timing control signals onto the pixel
data bus. ByteStream is the 8-bit version of this configuration. Because all timing
data is included on the data bus, a complete interface to a video controller can be
implemented in only nine pins: one for CLK x 2, and eight for data.
grammed high. When the RANGE bit is high, the chrominance pixels (both Cr
and Cb) are saturated to the range 2 to 253, and the luminance range is limited to
the range 16 to 253. In SPI Mode 2, the following values are inserted as control
codes to indicate video events (see Table 2-2): the chroma values of 255 and 254,
and the luminance values of 0 to 15. A chroma value of 255 indicates that the
associated luma pixel is a control code; a pixel value of 255 indicates that the
CbFlag is high (i.e., the current pixel is a Cb pixel). Similarly, a pixel value of 254
indicates that the luma value is a control code, and that the CbFlag is low (Cr
pixel).
precedence relationships, the HRESET code may be delayed by one pixel, so
HRESET can occur on a Cr or a Cb pixel. Also, at the beginning of a new field,
the relationship between VRESET and HRESET may be lost, typically with video
from a VCR. As a result, VRESET can occur during either a Cb or a Cr pixel.
Figure 2-10 demonstrates coded control for SPI Mode 2 (ByteStream).
128 indicates zero color information for Cr and Cb. Black is decimal 16 when
RANGE = 0 and code 0 when RANGE = 1.
Table 2-2. Description of the Control Codes in the Pixel Stream
Value
Luma
0x00
0x01
0x02
When using coded control, the RANGE bit and the CODE bit must be pro-
The first pixel of a line is guaranteed to be a Cb flag. However, due to code
Table 2-2 shows pixel data output ranges. Independent of RANGE, decimal
Figures 2-11 and 2-12 illustrate videotiming for SPI Modes 1 and 2.
Chroma
Value
0xFE
0xFE
0xFE
0xFF
0xFF
0xFF
D829BDSA
This is an invalid pixel; last valid pixel was a Cb pixel.
This is an invalid pixel; last valid pixel was a Cr pixel.
Cb pixel; last pixel was the last active pixel of the line.
Cr pixel; last pixel was the last active pixel of the line.
Cb pixel; next pixel is the first active pixel of the line.
Cr pixel; next pixel is the first active pixel of the line.
Video Event Description
VideoStream II Decoders
Bt829B/827B